This invention relates generally to calibrating touchscreens, and more particularly, to calibrating a touchscreen that recognizes a user touch as a unique audio profile.
Touch display systems, or “touch displays”, are provided for an increasing number of applications. Point of sale (POS), for processing transactions within a department store or restaurant, and point of information (POI), such as an electronic directory are common. For example, applications include airport passenger and baggage check-in, and kiosks located within a store that provide information about products and services. The kiosks also may be used to place an order and/or complete a purchase without the assistance of a sales person.
A touch display system has a display for visually presenting data to a user. A touchscreen is installed in front of the display, and the user selects and/or inputs data by touching the touchscreen at locations over software programmed buttons or icons in the displayed image.
One type of touchscreen technology is Acoustic Pulse Recognition (APR). Generally, an APR touchscreen recognizes the sound created when the glass is touched at a given position. A touch at each different position on the glass generates a unique sound. More specifically, one or more microphones on the glass or other substrate of the touchscreen detect the sound, represented as a signal, which results from a user touching a point on the glass.
A calibration file allows the user to successfully interact with the display that may be a graphical user interface (GUI) having buttons and icons or other graphical representations. Prior to normal use, X, Y coordinate positions on the touchscreen are associated with the signals generated when the particular X, Y coordinate is touched. The signals may be stored as a string of audio profiles in the calibration file. When a user touches the touchscreen, the resultant signal is compared to the audio profiles stored in the calibration file. The matching audio file is used to identify the location of the user's touch.
Each APR touchscreen varies slightly, and thus each APR touchscreen is individually calibrated or characterized to acquire and store a unique calibration file. During calibration, the APR touchscreen is loaded on a calibration machine specifically designed for the task. Many touches are generated, such as over 4000 touches, at known X, Y coordinate locations. For each of the over 4000 touches, a specific audio profile is stored and associated with the known X, Y coordinate location. This process is time consuming, due to both the number of coordinate locations which are touched as well as the time required on the calibration machine. Acquiring additional calibration machines is expensive, and thus throughput is limited by the calibration time as well as the number of available calibration machines.
Therefore, a need exists for decreasing the amount of time needed to calibrate an APR touchscreen. Certain embodiments of the present invention are intended to meet these needs and other objectives that will become apparent from the description and drawings set forth below.